Sperbeck is a former high school QB who is usually the one throwing the deep ball on double pass plays, and Williams-Rhodes, well even his pee-wee coaches knew his feet were what made him special.

"I never threw a ball in a football game, never," Williams-Rhodes said. "I told them I'm only good for about 25 yards and Thomas ran a little farther than that, but I was able to get it there."

The ball was a little wobbly but "I didn't have to break stride," said Sperbeck, who also caught an 85-yard touchdown pass from Brett Rypien (339 yards passing) and finished with 178 yards on five catches, all in the first half.

"It was nice," said Williams-Rhodes, who also hauled in his 200th career reception. "It was also my first touchdown this year. I've been looking to get into the end zone. So, I'll take a pass."

Williams-Rhodes acknowledged he had butterflies when the play was called on Boise State's fifth snap.

"I usually don't get nervous out there, but that was one of the plays I actually got nervous about," he said.

Running back Jeremy McNichols scored his FBS-leading 13th and 14th TDs of the season but left in the third quarter after his second score and didn't return, which Harsin called disconcerting.

McNichols, who scored on a 56-yard run in the first quarter, had 104 yards on 17 carries and caught six passes for 77 more yards. His 1-yard TD run made it 34-10 with 4:50 left in the third quarter, but he was hammered by defensive back Kevin Pierre-Louis as he crossed the goal line and was taken to the locker room for evaluation. He returned to the sideline about 15 minutes later but never re-entered the game.

"I don't know his status," Harsin said. "He didn't come back in, so we'll figure it out where he's at after tonight, but not coming (back) in, that's a problem."

The Broncos (5-1, 2-0 Mountain West) jumped out to a quick 17-0 lead before the Rams (2-4, 0-2) had even moved the chains.

"That's hard to come back from, especially against a Top 25 team," said Rams star receiver Rashard Higgins, who was held to three catches for 42 yards.

Two plays after Williams-Rhodes' TD throw to Sperbeck, safety Kameron Miles jarred the ball from running back Dalyn Dawkins and tackle Tyler Horn recovered it at the Rams 11. That led to Tyler Rausa's first field goal.

The Rams caught their first big break when a holding call negated Donte Deayon's 67-yard punt return to the Rams 11. Instead, the Broncos started the drive at their own 12.

It didn't matter. Boise State needed just four plays to score.

McNichols sped through a huge hole for a career-long 56-yard TD that made it 17-0.

Behind freshman quarterback Coleman Key, who split snaps with Nick Stevens, the Rams went on a 16-play, 75-yard drive that ate up nearly eight minutes. Key capped the drive with a 13-yard TD pass to Joe Hansley on the first play of the second quarter, snapping Boise State's shutout streak at seven quarters and 108 minutes.

"It felt like they had the ball forever," Sperbeck said. "The biggest thing was just keeping warm on the sideline so you can come out fast."

That, they did.

Fresh from all that time on the sideline, Rypien and Sperbeck hooked up for an 85-yard TD that made it 24-7.

Boise State senior safety Darian Thompson collected his fourth interception of the season and 18th of his career, tying the league record set by Eric Weddle.

"That is a tough pill to swallow when you get beat handily like that," Rams coach Mike Bobo said.